Math CentralQuandaries & Queries


What is a better way to express 400 in 7.5 billion?
My daughter has a rare condition, I want to know the answer to say “she is 1 in a ...”

Hi Emma,

You have 400 in 7,500,000,000. If you divide both by 100 that's 4 in 75,000,000. Now dividing both by 4 you get 1 in 18,750,000. Thus you daughter's condition affects 1 in 18.75 million.


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